Fractures of the distal tibia: minimally invasive plate osteosynthesis

Fractures of the distal tibia: minimally invasive plate osteosynthesis

Injury, Int. J. Care Injured (2004) 35, 615—620 Fractures of the distal tibia: minimally invasive plate osteosynthesis D.J. Redfern*, S.U. Syed, S.J...

171KB Sizes 5 Downloads 174 Views

Injury, Int. J. Care Injured (2004) 35, 615—620

Fractures of the distal tibia: minimally invasive plate osteosynthesis D.J. Redfern*, S.U. Syed, S.J.M. Davies Department of Orthopaedics, Frimley Park Hospital NHS Trust, Surrey, UK Accepted 9 September 2003

KEYWORDS Minimally invasive plate osteosynthesis; Plate fixation; Fracture; Tibia; Metaphysis

Summary Unstable fractures of the distal tibia that are not suitable for intramedullary nailing are commonly treated by open reduction and internal fixation and/or external fixation, or treated non-operatively. Treatment of these injuries using minimally invasive plate osteosynthesis (MIPO) techniques may minimise soft tissue injury and damage to the vascular integrity of the fracture fragments. We report the results of 20 patients treated by MIPO for closed fractures of the distal tibia. Their mean age was 38.3 years (range: 17—71 years). Fractures were classified according to the AO system, and intra-articular extensions according to Ru ¨edi and Allgo ¨wer. The mean time to full weight-bearing was 12 weeks (range: 8—20 weeks) and to union was 23 weeks (range: 18—29 weeks), without need for further surgery. There was one malunion, no deep infections and no failures of fixation. MIPO is an effective treatment for closed, unstable fractures of the distal tibia, avoiding the complications associated with more traditional methods of internal fixation and/or external fixation. ß 2003 Elsevier Ltd. All rights reserved.

Introduction Unstable fractures of the distal tibia with or without intra-articular fracture extension can present a management dilemma. Traditionally, there have been a variety of methods of management described and high rates of associated complications reported. Non-operative treatment can be technically demanding and may be associated with joint stiffness in up to 40% of cases as well as shortening and rotational malunion in over 30% of cases.14,20 Traditional operative treatment of such injuries is also *Corresponding author. Present address: 16 Byfield Road, Isleworth, Middlesex TW7 7AF, UK. Tel.: þ44-(0)20-8847-1370; fax: þ44-(0)20-8847-1370. E-mail address: [email protected] (D.J. Redfern).

associated with a high incidence of complications. Intramedullary nailing remains the gold standard for treatment of most diaphyseal fractures of the tibia. However, although some authors have described good results with intramedullary nailing in the treatment of distal peri-articular tibial fractures, it is generally considered unsuitable for such injuries, due to technical difficulty and design limitations.17,20 Traditional open reduction and internal fixation of such injuries results in extensive soft tissue dissection and periosteal injury and may be associated with high rates of infection, delayed union, and non-union.5,11,13,18,19,22 Similarly, external fixation of distal tibial fractures may also be associated with a high incidence of complications, with pin infection and loosening in up to 50% of cases and malunion rates of up to 45%.20 Minimally invasive plate osteosynthesis (MIPO) may offer biological

0020–1383/$ — see front matter ß 2003 Elsevier Ltd. All rights reserved. doi:10.1016/j.injury.2003.09.005

616

D.J. Redfern et al.

advantages. MIPO involves minimal soft tissue dissection with preservation of the vascular integrity of the fracture as well as preserving osteogenic fracture haematoma.3 MIPO techniques have been used successfully in the treatment of distal femoral fractures.9,10,23 Experience of the application of these techniques to fractures of the distal tibia is less extensive and opinion regarding optimal technique differs. Some authors advocate temporary external fixation prior to definitive MIPO and routine fixation of associated fibula fractures.7 Others advocate a more selective approach to the role of external fixation and fibular fixation.2

up available. Their mean age was 38.3 years (range: 17—71 years). There were 18 males and 4 females. The mechanism of injury was: fall (12); motorcycle accident (6); rugby/football injury (4) (see Table 1). Fractures were classified according to the AO system12 and distal intra-articular fracture extension classified according to Ru ¨wer18 ¨edi and Allgo (Table 1). All 20 fractures involved the distal onethird of the tibia and in 5 cases the fracture clearly extended distally in to the ankle joint (Ru ¨edi and Allgo ¨wer grade I in 3 cases and grade II in 2 cases). It is important to note that although 16/20 of the fractures were classified according to the AO system as 42 (diaphyseal), this is somewhat misleading as the ‘essence’ of these fractures was metaphyseal. Within the strict AO system12 definition of a metaphyseal fracture of the distal tibia (43), the centre of the fracture must lie within a square of sides equal to the widest metaphyseal distance, and the centre of many of our fractures lay just outside of the ‘metaphyseal square’ (Fig. 1a). The fracture pattern was however predominantly long oblique or long spiral and as such extended well into the distal metaphysis  extension into the joint (Fig. 1).

Purpose We report our experience with minimally invasive plate osteosynthesis in the treatment of closed, unstable fractures of the distal tibia that are unsuitable for intramedullary nailing.

Patients and methods

Indications for use of MIPO technique

We undertook a review of patients treated by MIPO for unstable fractures of the distal tibia in our hospital, between 1998 and 2001. Twenty-two patients were identified, of whom 20 had follow-

These included distal diaphyseal, or metaphyseal fractures of the tibia that were considered unsuitable

Table 1

Detailed patient data

Patient

Age (years)

Mechanism of injury

Fracture classification AO/R&A

Time to callus (weeks)

Time to FWB (weeks)

Time to union (weeks)

Complications

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

71 46 20 32 27 26 34 23 26 26 50 59 27 39 54 67 25 24 67 46

Fall Fall Football Motorcycle RTA Twisted Motorcycle RTA Rugby injury Rugby injury Football injury Motorcycle RTA Fall Fall Fall Fall Fell from wheelchair Fall Motorcycle RTA Motorcycle RTA Fall Fall

42-A2 42-B1 42-A2 42-A2 42-B1 42-C1 42-B1/grade 42-A1/grade 42-B1 42-B2 42-A1 43-A3/grade 42-A1 42-A1 42-B1 42-A1 43-B1 42-A1 43-B1/grade 43-B1/grade

8 7 8 8 8 8 10 10 8 8 11 8 12 12 8 8 10 8 10 10

12 13 12 14 8 20 12 12 10 17 9 14 13 12 N/A 12 10 13 10 12

26 24 20 22 20 20 24 18 28 29 24 26 24 20 24 20 20 22 24 20

— Metalwork discomfort — — — — Superficial infection Metalwork discomfort Metalwork discomfort — — Malunion CRPS (type 1) — — — — — — —

R&A: Ru ¨wer. ¨edi and Allgo

I I

II

I II

Fractures of distal tibia

617

Figure 1 (a) AP and lateral radiographs of the distal tibia for case 8 (42-A1, R&A grade 1). (b) AP radiograph (case 8) at 10 weeks post-operatively showing callus formation (A); AP radiograph (case 8) at 18 weeks showing radiological union (B).

for intramedullary nailing due to the distal nature of the fracture and/or intra-articular or peri-articular fracture extensions.

gical evidence of callus. All patients were followedup for a minimum of 12 months.

Operative technique Management protocol Initially, patients were managed in a plaster splint with elevation until definitive fixation could be undertaken. Surgery was undertaken on the next available theatre list and only delayed if soft tissue swelling or anaesthetic concerns dictated that this was necessary. Intravenous antibiotics were given at induction of anaesthesia and two doses following surgery. Post-operatively, patients were not routinely splinted unless deemed unlikely to comply with a partial weight-bearing regime. The majority of patients were encouraged to partial weight-bear on the limb (10—15 kg) from the first post-operative day. Early active and passive knee and ankle motion was encouraged. In the majority of cases, patients were discharged from hospital 24 h following surgery. Clinical and radiological review took place at 6—8 weeks to assess for evidence of callus formation. Patients were allowed to proceed to full weight-bearing on the basis of clinical and radiological evaluation but not before there was radiolo-

Surgery was performed with the patient supine on a radiolucent table. Routine preparation and draping of the injured limb was performed. Both indirect and direct techniques of fracture reduction were used depending upon the nature and pattern of the fracture. Reduction techniques employed included the use of manual traction, the AO femoral distracter, the AO articulated fracture distractor, and direct reduction with fracture reduction forceps across the fracture (via two stab incisions). A 2 cm incision was made proximal and distal to the fracture on the medial border of the tibia. An extraperiosteal, subcutaneous tunnel could then be fashioned between these two incisions using blunt dissection. A pre-measured and pre-contoured narrow 4.5 mm DCP was then positioned in this extra-periosteal subcutaneous tunnel (Fig. 2). Accurate plate contouring and positioning was confirmed by fluoroscopy. The length of plate selected is important and should be as long as is reasonably possible given the particular fracture pattern. As the length of plate is

618

D.J. Redfern et al.

Figure 2

Pre-contoured plate insertion with fracture reduction maintained by direct technique.

increased, the strength of the fixation construct is also increased.21 A cortical screw (4.5 mm) was then inserted through a screw hole at one end of the plate via the incisions already made for plate insertion. At this stage, axial fracture alignment was confirmed before inserting any further screws. Subsequent screws were inserted close to either side of the fracture via stab incisions. Further screws may be used depending upon the characteristics of the fracture. If possible, a lag screw was also inserted across the fracture (via the plate) in order to further reduce the fracture gap and add to the rigidity of the fixation. However, because the technique employs a bridge plating principle, interfragmentary lag screws were not felt to be obligatory. It is not necessary to place screws through all of the remaining holes in the plate as this does not further increase the strength or rigidity of the fixation construct4,21 but does require further skin incisions, providing more potential portals of entry for infection (Fig. 1b). The fibula was not fixed unless necessary for accurate reconstruction of length such as encountered with some severely comminuted fractures. With fractures extending into the ankle joint, careful attention was paid to restoration of the articular surface continuity and 3.5 mm cortical screws inserted through stab incisions or formal open exposure as required.

In only one case was it deemed necessary to fix the fibula in order to accurately reconstruct length before proceeding to minimally invasive plating of the tibia. The mean hospital stay was 6 days (range: 2—31 days). The mean time to radiological evidence of callus formation was 9 weeks (range: 7—12 weeks). Sixty percent of patients achieved radiological callus by 8 weeks and all by 3 months (Table 1 and Fig. 2). The mean time to full weight-bearing was 12 weeks (range: 8—20 weeks) and the mean time to union was 23 weeks (range: 18—29 weeks). There were no non-unions and one malunion in whom there was >58 of varus angulation. There were no cases of failure of fixation. Three soldiers have subsequently had their metalwork removed due to discomfort during training, and have reported no further symptoms. One patient required exchange of a distal screw that was too long and was impinging upon the distal tibia—fibula joint. A further patient developed type I complex regional pain syndrome (CRPS). He required guanethidine blocks to control his pain. There were no deep infections (one superficial infection which resolved on oral antibiotics). Sixteen of the 20 patients were employed at the time of their injury. Six patients were soldiers. All patients in this study have subsequently returned to their pre-injury occupations/level of activity.

Discussion Results Of the 20 patients presented, 12 were operated upon within 24 h of the injury, and 16 within 72 h of the injury. Surgery was delayed in the remaining four patients due to: transfer from another hospital (1); swelling at the site of injury (1); medical problems (1); and for further imaging (1). The surgery was performed by, or supervised by, one of six consultant orthopaedic surgeons in the department.

Favourable results have been described using minimally invasive plate osteosynthesis techniques for fixation of distal femoral fractures.9,10,23 Cadaveric and animal studies have emphasised the importance of minimising the degree of soft tissue damage in the region of long bone fractures.3,16,24 Recently, Borrelli et al.1 have demonstrated that the distal metaphyseal region of the tibia has a relatively rich extraosseous blood supply, provided primarily by

Fractures of distal tibia

branches of the anterior tibial and posterior tibial arteries. They also demonstrated that open plating in this region produces significantly greater disruption of this extraosseous blood supply than minimally invasive plate application. Helfet et al.7 described their experience with MIPO in 20 closed pilon fractures and advocated routine use of external fixation acutely, followed by definitive fixation 5—7 days later once the swelling has subsided. They also advocated the routine fixation of associated fibula fractures. They splinted the limb post-operatively but allowed toe-touch weight-bearing (20 lb) from the first post-operative day. Their patients achieved full weight-bearing at an average of 10.7 weeks (range: 8—16 weeks). Malunion occurred in 20% of cases although all patients had a good functional outcome and none required any further surgery. Collinge et al.2 have reported their experience using MIPO in 17 tibial shaft fractures. Twelve cases had open injuries and five of these required bone grafting at a later stage such that they suggested that this should be considered at an early stage in such injuries. The five patients with closed injuries had complete union after the index procedure with no cases of malunion or infection. These closed injuries all achieved a good functional outcome. They routinely splinted the limb post-operatively with weightbearing commenced at approximately 12 weeks. In this series, we confirm that good results can be obtained with this technique in the treatment of closed tibial fractures with intra-articular or periarticular fracture extensions, which are not suitable for intramedullary nailing. However, intramedullary nailing still remains the treatment of choice for most uncomplicated diaphyseal fractures of the tibia. We would not advocate the routine use of external fixation in the acute management of such injuries, except in some open injuries with extensive soft tissue damage. Early definitive surgery negates the need for any form of temporary fixation other than a POP back-slab for closed fractures. This avoids the added risk of complications arising from the use of such devices. It is our experience that fixation of the fibula is not necessary except to aid in reconstruction of length when there is extensive comminution of the tibial fracture. In the current series (and those of Collinge et al.2 and Koury et al.8), a 4.5 mm DCP has been used with satisfactory results. However, this is a relatively bulky implant and lower profile plate designs might be expected to result in a lower incidence of postoperative metalwork discomfort along this subcutaneous medial aspect of the tibia, especially in the region of the medial malleolus. This in turn may reduce the need for subsequent implant removal. Other recent developments in plate design include

619

pre-contoured and locking plates (e.g. LCP system, Synthes), which may offer significant advantages. The ‘internal fixator’ design of locking plates has the advantage that screw insertion does not draw the bony fragments to the plate (as occurs with traditional non-locking plates) and hence, the precise contouring of the plate is less important in achieving accurate fracture reduction.6,15 For the same reason, the footprint of the locking plates should also be significantly smaller than traditional non-locking plates, hence preserving periosteal blood supply to the fracture.6 In the majority of cases, we have found it possible to safely mobilise patients, partial weightbearing (10—15 kg), from the first post-operative day without external splintage of the limb. This also allows early mobilisation of the knee, ankle and subtalar joints.

Conclusion Whilst intramedullary nailing still remains the treatment of choice for most uncomplicated diaphyseal fractures of the tibia, minimally invasive plate osteosynthesis offers a reliable and reproducible technique in the treatment of closed unstable fractures of the distal tibia with intra-articular or periarticular fracture extensions. This technique may avoid the significant complications encountered with more commonly used techniques of internal fixation and external fixation in such injuries.

References 1. Borrelli J, Prickett W, Song E, Becker D, Ricci W. Extraosseous blood supply of the tibia and the effects of different plating techniques: a human cadaveric study. J Orthop Trauma 2002;16:691—5. 2. Collinge C, Sanders R, DiPasquale T. Treatment of complex tibial periarticular fractures using percutaneous techniques. Clin Orthop 2000;375:69—77. 3. Farouk O, Krettek C, Miclau T, Schandelmaier P, Guy P, Tscherne H. Minimally invasive plate osteosynthesis and vascularity: preliminary results of a cadaver injection study. Injury 1997;28:S-A7—S-A12. 4. Field RJ, To ¨rnkvist H, Hearn TC, et al. The influence of screw omission on construct stiffness and bone surface strain in the application of bone plates to cadaveric bone. Injury 1999;30:591—8. 5. Fisher WD, Hambledon DL. Problems and pitfalls of compression fixation of long bone fractures: a review of results and complications. Injury 1978;10:99—107. 6. Frigg R. Locking compression plate (LCP). An osteosynthesis plate based on the dynamic compression plate and point contact fixator (PC-Fix). Injury 2001;32:S-B63—6. 7. Helfet DL, Shonnard PY, Levine D, Borrelli J. Minimally invasive plate osteosynthesis of distal fractures of the tibia. Injury 1997;28:S-A42—8.

620

8. Koury A, Liebergall M, London E, Mosheiff R. Percutaneus plating of distal tibial fractures. Foot Ankle Int 2002;23: 818—24. 9. Krettek C, Schandelmaier P, Miclau T, Tscherne H. Minimally invasive percutaneous plate osteosynthesis (MIPPO) using the DCS in proximal and distal femoral fractures. Injury 1997;28:S-A20—30. 10. Krettek C, Schandelmaier P, Miclau T, Bertram R, Holmes W, Tscherne H. Transarticular joint reconstruction and indirect plate osteosynthesis for complex distal supracondylar femoral fractures. Injury 1997;28:S-A31—41. 11. McFerran MA, Smith SW, Boulas HJ, Schwartz HS. Complications encountered in the treatment of pilon fractures. J Orthop Trauma 1992;6:273—85. 12. Muller ME, Nazarian S, Koch P, Schatzker J. The comprehensive classification of fractures of long bones. Berlin: Springer-Verlag; 1990. 13. Olerud S, Karlstrom G. Tibial fractures treated by AO compression osteosynthesis. Acta Orthop Scand Suppl 1972; 1:1—104. 14. Oni OO, Stafford H, Gergg PJ. A study of diaphyseal fracture repair using tissue isolation techniques. Injury 1992;23: 467—70. 15. Perren SM. Editorial. Injury 2002;33:S-A-VI—S-A-VII. 16. Rhinelander F. The normal microcirculation of diaphyseal cortex and its response to fracture. J Bone Joint Surg Am 1968;50A:784—800.

D.J. Redfern et al.

17. Robinson CM, McLaughlan GJ, Mclean IP, Court-Brown CM. Distal metaphyseal fractures of the tibia with minimal involvement of the ankle. Classification and treatment by locked intramedullary nailing. J Bone Joint Surg Br 1995;77B:781—7. 18. Rue ¨di T, Allgo ¨wer M. Fractures of the lower end of the tibia into the ankle joint. Injury 1969;1:92. 19. Rue ¨di T, Allgo ¨wer M. The operative treatment of intraarticular fractures of the lower end of the tibia. Clin Orthop 1979;138:105—10. 20. Russell TA. Fractures of the tibia and fibula. In: Rockwood CA, Green DP, Buckolz RW, Heckman JD, editors. Fractures in adults. 4th ed. Philadelphia: Lippincott; 1996. p. 2139— 57. 21. Sanders R, Haidukewych GJ, Milne T, et al. Minimal versus maximal plate fixation techniques of the ulna: the biomechanical effect of number of screws and plate length. J Orthop Trauma 2002;16:166—71. 22. Tornetta III P, Weiner L, Bergman M, et al. Pilon fractures: treatment with combined internal and external fixation. J Orthop Trauma 1993;7:489—96. 23. Wenda K, Runkel M, Degreif J, Rudig L. Minimally invasive plate fixation in femoral shaft fractures. Injury 1997;28:SA13—9. 24. Whiteside L, Lesker PA. The effects of periosteal and subperiosteal dissection. J Bone Joint Surg Am 1978;60A: 26—30.